As of 2015, the Carrier Comfort 80 gas furnace costs approximately $890, with professional installation bringing the average cost of replacement to $1,950. Carrier also manufactures the Infinity 80 and Performance Boost 80 models that retail at roughly $1,495.
The Infinity 80 and Performance Boost 80 are both equipped with variable-speed blowers; with professional installation, the cost for one of these units is approximately $2,480.
Carrier's most efficient gas furnace lines are the Comfort 95, Performance 96 and Infinity 96. These 95 percent energy efficient units have an average unit sticker of $1,710, with installation costs bringing the total to approximately $4,200.